12 Volt cooler

[CindyH]

Hello,
I'm trying to decide whether to buy a small (15-17 L) 12V cooler to use in my Ford Ranger when not pulling my trailer, and to augment my trailer fridge when I am towing.

Right now I'm looking at a Coleman and a Koolatron. Don't know the last one. I'm interested in your opinions about their relative performance. Also, I don't know the Koolatron brand. It seems imperative that I also purchas a 120V to 12V Converter so that I can plug it in at home or on the road at a campsite with shore power. Are the 12V coolers worth the expense?
Thanks for your input.
Cindy

[Pahaska]

I bought one at a second hand store; I don't remember the brand. It came with the 120v cord and 12v cord. We really like it. I precool 9 cans of soda and then out it behind the front seat. When not travelling, it sits on my workbench so I can grab a can of cold soda when working in the yard.

When at a campsite, I put it on top of the fridge and plug it into 120v for precooling sodas. If we go on a day trip, we take it with sandwiches and the like.

They are all based on Peltier junctions and work essentially the same. The one I have can be found new at HD for about $45.

[ViewRVs]

We have the Coleman. It's now a necessity. We keep it in out Honda Odyssey for cold stuff from the store. We also use it when taking stuff to the RV in storage. It will keep stuff cold. It is not a freezer. I also recommend getting the 120v adapter.

[sjptak]

We also have a Coleman. We use it all the time in the Gladiator. When we go shopping, we don't have to rush home to put perishables in the fridge, we can finish up on errands. We can also travel further with perishables

BTW, what is a Peltier Junction?

[Pahaska]

is what all of these coolers use to move heat in or out (most can be used as heaters as well as coolers).

A Peltier junction is a flat semiconductor module that moves heat from one side to the other when DC current is applied. It also will generate current if there is a temperature differential between the two sides, but this is of no interest here.

In one of these coolers, there is usually a heat sink and a fan to cool the external (typically hot) side of the junction. On the inner surface of the cooler, there is usually aluminum plate that is screwed to the cold side with thermal paste between. Sometimes, on the larger units, there is a second heat sink and fan inside.

It is a great way to run a cooler with no moving parts or flames.

[Silvertwinkie]

I always wondered it those things really worked well!



Eric

[Tripp]

Some of the off road guys use a cooler made by ARB. As I understand it, it'll FREEZE your food if you want it to! Big dollars though.

I see them advertised all the time in the various truck mags, just can't remember the US vendor.

Tripp

[59toaster]

Originally posted by Tripp
Some of the off road guys use a cooler made by ARB. As I understand it, it'll FREEZE your food if you want it to! Big dollars though.

I see them advertised all the time in the various truck mags, just can't remember the US vendor.

Tripp

Yeah those ARB units are EXPENSIVE! One of the guys in my 4x4 club has one. We call him the Ice cream man. He usualy has it packed full of Ice cream and gives it out when we have lunch. They work and they will freeze. They can maintain freezing inside in the mid 90's outside temp. Just need to keep them in the shade.

My local 4x4 shop carries them and I think four wheel performance also carries them.

On the other units:

It's my understanding that they can make about a 40 degree drop in temp. So if the temp outside the unit is 90 they can get down to 50 inside. If your running them in the car while you have the A/C on they do pretty good. Sitting in the sun on a 95deg day they may only get items down to 60 degrees.

[dtbw]

We have the 35qt Igloo heat/cool version and love it. We were planning to buy one new when we found a practically new one at our subdivision garage sale last fall (paid $25, but it was missing the shelves). Ordered shelves from Igloo along with a 120V converter and a device that prevents the cooler from draining the car battery (ie using it on 12V without the motor running). We love the big size and the fact that we can use it as a chest or upright unit (normally we use it as a chest to mimimize the loss of the cold air when opening. We also found a trick to using it for frozen foods. Cool it down for a day or so empty(in the cool of the house), then buy a slab of dry ice (5lbs) and put it in the unit, then add your frozen foods (have kept foods frozen HARD for way over a week this way). Without the dry ice trick, you will find it is, at best, a cooler during the summer. Ours is an indepensible part of our A/S rig as we also use it for beer, pop and wine for those week end rallies and parties.

[sjptak]

"It will also generate current if there is a temperature differential between the two sides"

Is that why when I remove the plug from AC, the charge LED will remain on and the squirrel cage keeps turning? I found it pretty curious. I had to take off the cover to see what was under there. The Coleman I have has the heat sinks and fan both in and outside of the unit.

59Toaster, you are right about that 40 degree drop. Even with that, it still has a use for the sodas and beer, stuff that won't spoil from a little warmth. I wouldn't trust it with meat in it for two days in the middle of August, though.

[Pick]

Hmmmm, now you all got me wondering.........I bought one of those $100 mini fridges for my shop. I'll have to check the current draw on the compressor, to see if it is possible and practical to run the little bugger on the 400 watt Vector inverter.

[garry]

My son has one and likes it for trips but on the down side he said it will run a battery down fairly quickly without the engine running.

Garry .

[Pahaska]

Is that why when I remove the plug from AC, the charge LED will remain on and the squirrel cage keeps turning?

The chip is generating voltage because of the cold box and the warm outside air. As the temperature equalizes, the effect should fade away.

[JeffandSuzanne]

We had the 35 qt. Igloo. . .it quit working during the first use. I had to send it to Igloo (at my cost-UPS $12.00) for warranty repair. When returned, it never got anything any colder than a conventional ice chest with 10 lbs of ice in it. I had all the cords and adapters; and the "battery saver" had a disclaimer that it wouldn't work with some auto models, but didn't specify which ones. It ran my battery down overnight in my 1999 Ford E-250 van during a trip. It wasn't worth the hassle so I quit using the cooler and sold the whole lot for $35.00 in a garage sale to help cut my loss! Hope other folk have had better luck!

[Pick]

Hmmm....another thought. Since my fridge is AC only, maybe I should just run a 120 cord from the Airstream to the bed of the truck, and run the EU2000i in the eco mode while enroute. The fridge draws 1.9 amps and starting current is 9 amps. Hard part would be positioning the Honda so it does not roll over during transit, while maintaining proper venilation.

[dtbw]

Jeffand Suzanne,
Sorry that you had a bad experience with the Igloo (sounds like we have the exact same setup). Maybe part of it was expectation. This type of unit is not meant to be a freezer, but rather a cooler without the use of ice. Comparing it a ice chest with 10#s of ice is exactly what this this type of cooler is capable of delivering. Not sure why the voltage cutoff did not work to prevent running down your truck battery, as it has worked perfectly for us ('02 Ford Explorer SportTrac) over several trips. The Igloo draws about 3 amps, so overnight use should only drain 35-40 amp-hours max (assuming 12 hours) and that should not have killed your battery. (vehicle batteries are typically 80-100 amp-hour). Not knowing the age of your truck battery at the time of the incident, it is impossible to know what happened, but batteries in vehicles are meant for starting (ie short, high current drains, followed by quick recharges). With vehicle batteries even a year old, draining them over a longer period and to a deeper level, can often expose issues that would not have shown up until later in the life of the battery. Older vehicle battery's current capacity degrades over time as sulfer builds up in the plates. This process means that the remaining current capacity of a battery at any given voltage (voltage is what the disconnect unit monitors) degrades. There is a point in a lead acid battery life cycle where there is precious little capacity beyond the needs of starting. So, you allow a device such as a cooler to pull 35-40 AmpHrs out, on top of what the residual vehicle electronics draw (even when the vehicle is off), and you have the situation where there is insufficent current capability to turn over the starter.

BTW, there is a way to greatly extend the life of a lead acid battery (beyond the normal stuff such as water, corrosion, etc). Pushing the battery voltage to 15.5V or so for several hours every couple of months (known as equalization) results in the build up of sulfur in the plates to reverse (ie the sulfur in the plates goes back into the sulfuric acid solution where it belongs). This makes more of the lead surface of the plates available for the chemical reaction. Unfortunately, car alternator systems do not push the voltage much above 14V, so the way to perform this on a tow vehicle battery is using an external charger with the equalization capability.

[eikel1we]

Our daughter had a Koolatron first and we liked hers so much we bought our own. It gets good and cold and we, too, use ours for food shopping on hot days and while taking food to the cottage. We have an extension cord and can put it in the way-back of the Suburban. Cupcake has two 12v plugs so we could use it in there also. Has anyone tried the heated mode yet?

sue

[Pahaska]

I tried it as an experiment when I first bought the cooler. It got nice and warm. Except for maybe heating something like baby bottles, I don't see much use for the heated mode. It didn't really get hot enough for food.

[sjptak]

on several occasions. My wife's mother lives about an hours drive from here and we have picked up warm trays of lasagna or eggplant and the such for family functions there. I did a good job of keeping things warm until we got there, even in a CT December while it was in the trunk. The food wasn't hot, but at a very warm serving temperature, just the way I like it.

[eikel1we]

That's good to know. You could wrap an oven dish to protect the interior of the cooler and arrive with a still warm dish to pass etc. This is good to know - I pretty much forgot about the heat feature and will have to test it out.

suz